Testing for Battery charging

[AnglersEdgeNY]

86 johnson 225
How would I go about testing if my batteries are charging with a Blue Sea Add a Battery System installed.
With the engine running I tested across the batt terminals and got a reading of 12.6ish volts. I know the relay controls the charging some how.
I'm a little suspicious because my tach isn't working.
I did the test as Joe Reeves described for the 35 amp rectifier and the results were that my tach is bad. I guess I just want to make sure I'm charging the batteries.

Mike

 

[F_R]

Re: Testing for Battery charging

You aren't charging at that voltage.

 

[AnglersEdgeNY]

Re: Testing for Battery charging

Thats what I thought, but then I researched about the auto charging relay that came with the system and it states that:
"ACR's or Automatic Charging Relays are automatic switches that close when the voltage on one of the batteries rises to a level (normally 13.2V to 13.7V) indicating the battery is connected to a charge source and is partially or fully charged. The switch then closes and shares the charging current with the other battery until the voltage drops to some lower level (normally 12.4 to 13.1 depending on model) and the switch opens. This prevents discharging both batteries when there is not enough current to charge both batteries."

The battery that I was testing on was new. So if I understand that description above correctly when the battery is charged the switch shuts off and charges the other battery.

The engine has only been run twice so far for a short time, so maybe that batt has not been dischaged enough for a charge.

 

[F_R]

Re: Testing for Battery charging

The way I read it, the charging voltage should be at least 13.2 volts, then it starts charging both batteries. But if voltage goes below that, it goes back to just charging the main one.